Results 11 to 20 of about 16,571 (112)
Shuitu Baochi Xuebao, 2022 以北京市重度火烧迹地油松人工林为对象, 基于原位采样法和室内浸泡法于2020年7—12月在对照样地和火烧样地采集凋落物样品并测定分析其现存量、持水量、有效拦蓄量等指标, 探究林火干扰下凋落物的分解及水文效应, 为更好促进森林水源涵养功能以及水土保持功能提供依据。结果表明: (1)油松人工林半分解和完全分解层凋落物平均现存量分别为16.18(叶占比>80%), 31.88 t/hm2, 平均厚度分别为2.77, 2.79 cm; 与对照相比, 火烧后半分解层凋落物厚度及现存量分别降低39.35%, 53 ...
邱聪, 秦倩倩, 郑大柽, 刘艳红
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Genomic responses to increased temperature and pollinator selection in Brassica rapa L.
New Phytologist, Volume 250, Issue 2, Page 1231-1247, April 2026.Summary Rapid environmental change reshapes both abiotic stress and biotic interactions, yet it remains unclear how these combined forces structure plants' genomic adaptation. In particular, the joint influence of temperature and pollinator identity, two ecological axes undergoing simultaneous global shifts, has rarely been quantified at genomic ...
Yanqian Ding, Florian P. Schiestl
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Shuitu Baochi Xuebao, 1996 水土保持林有效覆盖率是水土保持林建设中的一个重要指标。该术语虽出现较早且已被逐渐采用，但由于缺乏严格的定义和统一确定标准，以至水土保持林有效覆盖率数值从３０％～７５％，这严重影响了水土流失区林业生产的宏观决策。通过对水土保持林系统的详细分析，定义了水土保持林有效覆盖率为在一定防护范围内的土壤流失量等于允许流失量时的森林覆盖率：ａｅ－ｂＦ＝ＳＬＡ。并指出有效覆盖率的确定涉及２个方面、３个步骤；水土保持林有效覆盖率为时间和空间的函数。此外还以黄土高原水土流失区为例，介绍了水土保持林有效覆盖率的确定方法。
郭忠升
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Shuitu Baochi Xuebao, 2021 基于3年连续冬小麦-夏玉米覆膜轮作试验，通过校验之后的AquaCrop模型设置不同水平的播前土壤墒情，模拟研究关中地区多年历史气候条件下旱作覆膜夏玉米生长和水分利用对播前土壤墒情的响应规律，拟基于播前土壤墒情初步建立覆膜与否的判断标准。结果表明，当土壤初始含水率≤70%田间持水量，关中地区夏玉米覆膜产量波动剧烈；覆膜增产率随着降水的增加呈增加趋势。随着土壤初始含水率的增加，覆膜增产效果越来越明显，且趋于稳定；然而覆膜措施的增产效果对降水量越来越不敏感，最终呈稳定趋势。当播前土壤底墒达到80%~85 ...
徐志鹏 +7 more
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT High‐entropy alloys (HEAs) have attracted considerable interest from researchers owing to their tunable chemical compositions, exceptional structural stability, and promising catalytic properties. However, their large‐scale application is often hindered by complex manufacturing techniques and poor durability.
Sheng Guo +9 more
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Shuitu Baochi Xuebao, 2006 对火力楠、荷木和黎蒴的凋落物的储量、持水量、持水率和吸水速率进行了研究。结果表明，火力楠、荷木和黎蒴林地的凋落物干重分别为10488，5159，5583kg／hm^2。浸泡2h前凋落物持水量呈现火力楠林地〉黎蒴林地〉荷木林地，浸泡2h后为黎蒴林地〉火力楠林地〉荷木林地。3种林分中黎蒴林地的凋落物最大持水量在居首位，达17709kg／hm^2，火力楠林地居中，为16576kg／hm^2，荷木林地较小，为13374kg／hm^2。不同浸泡时间段的凋落物持水率均呈现黎蒴林地〉荷木林地〉火力楠林地。火力楠 ...
彭耀强 +4 more
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT The development of highly efficient and stable nonprecious metal electrocatalysts for the acidic oxygen evolution reaction (OER) is crucial to advance proton exchange membrane (PEM) water electrolysis. In this work, a dual synergistic strategy was proposed by constructing a Ce‐modified MnO2/MnO heterostructure.
Chuanbin Li +7 more
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亚热带喀斯特森林的水土保持效益研究——以贵州茂兰国家级自然保护区为例
Shuitu Baochi Xuebao, 2002 茂兰喀斯特森林是亚热带地区幸存下来的一片面积最大 ,分布最集中 ,原生性最强的喀斯特森林。通过一年多时间的连续观测发现 :在 15 93.2 m m的年总降雨量中 ,有 2 0 7.4 mm被林冠截流 ,占 13% ;有 119.1m m为树干径流 ,占 7.5 % ;森林穿透雨为 12 6 6 .7m m,占 79.5 %。枯枝落叶的最大持水率可达 2 35 .6 7% ,岩面苔藓的最大吸水率可达 6 5 0 .35 % ,腐殖土的最大持水率为 6 4 .4 3% ,而钙质土的最大持水率仅为 4 5 .
冉景丞 何师意 曹建华 熊志斌 陈会明
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT In conventional piezoceramics, the coordinated change between the dielectric constant (εr) and the piezoelectric charge constant (d33) usually limits the piezoelectric voltage constant g33 (g33 = d33/εr), a critical figure of merit for piezoelectric sensors.
Xiaoying Feng +7 more
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Shuitu Baochi Xuebao, 2005 通过对高吸水性树脂在不同肥料溶液中吸水倍率和肥料养分吸持量的测定,研究了不同吸水倍率的聚丙烯酰胺型、聚丙烯酸盐型、淀粉接枝型高吸水性树脂与氮、磷、钾肥料的相互影响。结果表明:化学肥料能显著降低高吸水性树脂的吸水倍率,并随肥料浓度的增加,高吸水性树脂吸水倍率显著降低。但不同肥料品种对高吸水性树脂吸水倍率的影响程度不同:供试肥料对高吸水性树脂的影响程度依过磷酸钙、磷酸一铵、硫酸钾、氯化铵、硫酸铵、氯化钾、尿素顺序递减。高吸水性树脂在水中溶胀时,在吸收大量水的同时,也吸持溶解在水中的肥料分子或离子 ...
杜建军 王新爱 廖宗文 苟春林 毋永龙
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